Section 1.4 of the Power ISA v3.0B states that both of these
instructions are single-copy atomic. As we cannot (yet) issue
128-bit loads within TCG, use the generic helpers provided.
Since TCG cannot (yet) return a 128-bit value, add a slot within
CPUPPCState for returning the high half of a 128-bit return value.
This solution is preferred to the helper assigning to architectural
registers directly, as it avoids clobbering all TCG live values.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>